Since their introduction, the number of services and features for cellular telephones has steadily increased while the cost of ownership and operation has decreased. At first, these mobile telecommunication devices operated on analog wireless networks that enabled voice communication and simple paging features. Later, digital wireless networks were introduced for cellular telephones to provide more advanced features for voice and data communication, such as encryption, caller identification and transmitting and receiving short message service (SMS) text messages. More recently, some cellular telephones enable the browsing of web pages on the Internet or other on-line services.
The functionality of cellular telephones continues to increase. Some cellular telephones incorporate many of the features originally provided for in handheld electronic devices, such as personal digital assistants (PDAs). Relatively simple PDA features such as keeping a list of contacts, a calendar, appointments, and the like have been generally integrated into recent cellular telephone models.
Along with the increased services and features, it is common for individuals to own a cellular telephone and use it for daily communications. Individuals are no longer restricting the use of their cellular telephone to strictly business or emergency calls. They are talking with their friends about what they are currently doing, what they are listening to on the radio, watching on television, viewing on the World Wide Web, and the like. The user may want tell their friends what they are current doing and experiencing, and to know what their friends are doing, all without having to make numerous phone calls.
However, unlike desktop computers, laptop computers and PDA, cellular telephones typically have limited input capabilities. That is, inputs typically have to be made through a limited number of inputs keys, e.g. through a 12-key numeric keypad. Thus, a great need exists to enable the rich functionalities, such as non-verbal conversing with users of other cellular telephones, to be consumable in an efficient and friendly manner under the context of limited input keys.